Characterization by XPS and XAS of supported Pt/TiO2-CeO2 catalysts

Abstract
TiO2 and CeO2 are will known for inducing strong metal‐support interactions J(SMSI) of a different nature when used as supports for Pt catalysts. X‐ray photoelectron spectroscopy analysis of mixtures of TiO2CeO2 oxide supports (80:20 and 20:80) reveals at the surface a remarkable stabilization of cerium in the +3 oxidation state; the stabilization is more pronounced with lower cerium oxide concentration. X‐ray absorption spectroscopy measurements done on the LIII edge show the same variation as a function of cerium oxide concentration, but in the bulk the reduction is much lower. Cerium in Pt/TiO2CeO2 catalysts exhibits the same behaviour.